Overriding elastic values for graphical objects

Abstract

To process the layout of graphical objects, elastic data structures are established for the graphical objects to define minimum and preferred sizes, stretch properties and compression properties. One application of elastics is with respect to text blocks where preferred width and compressibility of each text block is a function of the amount of text in the text block. Composite graphical objects include elastic properties computed from their components through add and max operations which are dependent on relative elasticities of the components. The positions of origins within graphical objects are defined by pairs of elastics in each of two dimensions. The default width or height preference of a graphic object can be overridden. Overriding elastics is an effective mechanism for altering the display characteristics of graphical objects while preserving certain display relationships. The elastics and dimensions of graphical objects are processed in a three pass layout negotiation. In the first pass, preferred sizes and elasticities of the graphical objects are computed along a first dimension. In a second pass, size values of the graphical objects along the first dimension are computed from the preferred sizes and elasticities, and preferred sizes and elasticities of the graphical objects along a second dimension are computed based on the size values of the graphical objects along the first dimension. In a final pass, size values of the graphical objects along the second dimension are computed from the preferred sizes and elasticities.

What is claimed is:  
     
         1 . A method for overriding an original layout elastic for a graphical object comprising: 
 receiving a new layout elastic for a dimension of the graphical object;    storing the new layout elastic;    determining a resulting layout elastic from the new layout elastic and the original layout elastic; and    returning the resulting layout elastic.    
     
     
         2 . The method of  claim 1  wherein the dimension is height.  
     
     
         3 . The method of  claim 1  wherein the dimension is width.  
     
     
         4 . The method of  claim 1  wherein the new layout elastic is defined as an OriginElastic and the determining step comprises: 
 copying the stored new layout elastic to the resulting layout elastic.  
 
     
     
         5 . The method of  claim 1  wherein the new layout elastic is defined as a rigid elastic representing a linear measurement and the determining step comprises: 
 accessing elastic parameters of the new layout elastic;  
 accessing elastic parameters of the original layout elastic;  
 computing override elastic parameters from the elastic parameters of the new layout elastic and the elastic parameters of the original layout elastic; and  
 storing the override elastic parameters in the resulting layout elastic.  
 
     
     
         6 . The method of  claim 5  wherein the elastic parameters comprise: 
 the graphical object's minimum size;  
 the graphical object's preferred size;  
 the graphical object's compressibility coefficient;  
 the graphical object's compress order;  
 the graphical object's stretchiness coefficient; and  
 the graphical object's stretch order.  
 
     
     
         7 . The method of  claim 1  wherein the resulting layout elastic is a non-rigid elastic.  
     
     
         8 . The method of  claim 1  wherein the elastic parameters of the resulting layout elastic are set so that applying an elastic add operation to the resulting layout elastic, the add operation adding first and last components of the resulting layout elastic would yield an elastic equal to the new layout elastic.  
     
     
         9 . The method of  claim 1  wherein the original layout elastic is defined as an OriginElastic and the resulting layout elastic is defined as an OriginElastic and wherein: 
 a preferred size of a first component of the resulting layout elastic is set equal to result of divide(A,B,x) operation where:  
 A is a first component of the original layout elastic;  
 B is a last component of the original layout elastic; and  
 x is a preferred size of the new layout elastic.  
 
     
     
         10 . The method of  claim 1  wherein the original layout elastic is defined as an OriginElastic and the resulting layout elastic is defined as an OriginElastic and wherein: 
 a minimum size of a first component of the resulting layout elastic is set equal to result of divide(A,B,y) operation where:  
 A is a first component of the original layout elastic;  
 B is a last component of the original layout elastic; and  
 x is a minimum size of the new layout elastic.  
 
     
     
         11 . The method of  claim 1  wherein the original layout elastic is defined as an OriginElastic and the resulting layout elastic is defined as an OriginElastic and wherein when a stretch order of a first component of the original layout elastic and a stretch order of a last component of the original layout elastic are equal, then a ratio between a stretchiness coefficient of a first component of the resulting layout elastic and a stretchiness coefficient of a last component of the resulting layout elastic equals a ratio between a stretchiness coefficient of a first component of the original layout elastic and a stretchiness coefficient of a last component of the original layout elastic.  
     
     
         12 . The method of  claim 1  wherein the original layout elastic is defined as an OriginElastic and the resulting layout elastic is defined as an OriginElastic and wherein: 
 when a stretch order of a first component of the original layout elastic is greater than a stretch order of a last component of the original layout elastic,  
 then a stretch order of a first component of the resulting layout elastic is greater than a stretch order of a last component of the resulting layout elastic; and  
 when a stretch order of a first component of the original layout elastic is less than a stretch order of a last component of the original layout elastic,  
 then a stretch order of a first component of the resulting layout elastic is less than a stretch order of a last component of the resulting layout elastic.  
 
     
     
         13 . An apparatus for overriding an original layout elastic for a graphical object comprising: 
 a new layout elastic for a dimension of the graphical object; and    an evaluator determining a resulting layout elastic from the new layout elastic and the original layout elastic.    
     
     
         14 . The apparatus of  claim 13  wherein the dimension is height.  
     
     
         15 . The apparatus of  claim 13  wherein the dimension is width.  
     
     
         16 . The apparatus of  claim 13  wherein the new layout elastic is defined as an OriginElastic and the evaluator further comprises: 
 a mechanism to copy the new layout elastic to the resulting layout elastic.  
 
     
     
         17 . The apparatus of  claim 13  wherein the new layout elastic is defined as a rigid elastic representing a linear measurement and the evaluator further comprises: 
 elastic parameters of the new layout elastic;  
 elastic parameters of the original layout elastic;  
 a mechanism that computes override elastic parameters from the elastic parameters of the new layout elastic and the elastic parameters of the original layout elastic; and  
 a mechanism that stores the override elastic parameters in the resulting layout elastic.  
 
     
     
         18 . The apparatus of  claim 17  wherein the elastic parameters comprise: 
 the graphical object's minimum size;  
 the graphical object's preferred size;  
 the graphical object's compressibility coefficient;  
 the graphical object's compress order;  
 the graphical object's stretchiness coefficient; and  
 the graphical object's stretch order.  
 
     
     
         19 . The apparatus of  claim 13  wherein the resulting layout elastic is a non-rigid elastic.  
     
     
         20 . The apparatus of  claim 13  wherein the elastic parameters of the resulting layout elastic as set such that an elastic equal to the new layout elastic is constructed by applying an elastic add operation to the resulting layout elastic, the add operation adding first and last components of the resulting layout elastic.  
     
     
         21 . The apparatus of  claim 13  wherein the original layout elastic is defined as an OriginElastic and the resulting layout elastic is defined as an OriginElastic and wherein: 
 a preferred size of a first component of the resulting layout elastic is set equal to result of divide(A,B,x) operation where:  
 A is a first component of the original layout elastic;  
 B is a last component of the original layout elastic; and  
 x is a preferred size of the new layout elastic.  
 
     
     
         22 . The apparatus of  claim 13  wherein the original layout elastic is defined as an OriginElastic and the resulting layout elastic is defined as an OriginElastic and wherein: 
 a minimum size of a first component of the resulting layout elastic is set equal to result of divide(A,B,y) operation where:  
 A is a first component of the original layout elastic;  
 B is a last component of the original layout elastic; and  
 x is a minimum size of the new layout elastic.  
 
     
     
         23 . The apparatus of  claim 13  wherein the original layout elastic is defined as an OriginElastic and the resulting layout elastic is defined as an OriginElastic and wherein 
 when a stretch order of a first component of the original layout elastic and a stretch order of a last component of the original layout elastic are equal,  
 then a ratio between a stretchiness coefficient of a first component of the resulting layout elastic and a stretchiness coefficient of a last component of the resulting layout elastic equals a ratio between a stretchiness coefficient of a first component of the original layout elastic and a stretchiness coefficient of a last component of the original layout elastic.  
 
     
     
         24 . The apparatus of  claim 13  wherein the original layout elastic is defined as an OriginElastic and the resulting layout elastic is defined as an OriginElastic and wherein: 
 when a stretch order of a first component of the original layout elastic is greater than a stretch order of a last component of the original layout elastic,  
 then a stretch order of a first component of the resulting layout elastic is greater than a stretch order of a last component of the resulting layout elastic; and  
 when a stretch order of a first component of the original layout elastic is less than a stretch order of a last component of the original layout elastic,  
 then a stretch order of a first component of the resulting layout elastic is less than a stretch order of a last component of the resulting layout elastic.  
 
     
     
         25 . A computer program product comprising:  
       a computer usable medium for overriding an original layout elastic for a graphical object; 
 a set of computer instructions embodied on the computer usable medium, including instructions to:  
 receive a new layout elastic for a dimension of the graphical object;  
 store the new layout elastic;  
 determine a resulting layout elastic from the new layout elastic and the original layout elastic; and  
 return the resulting layout elastic.  
 
     
     
         26 . A propagated signal carried on an electromagnetic waveform, the signal comprising a set of computer program instructions to: 
 receive a new layout elastic for a dimension of the graphical object;    store the new layout elastic;    determine a resulting layout elastic from the new layout elastic and the original layout elastic; and    return the resulting layout elastic.    
     
     
         27 . An apparatus for overriding an original layout elastic for a graphical object comprising: 
 a means for receiving a new layout elastic for a dimension of the graphical object;    a means for storing the new layout elastic;    a means for determining a resulting layout elastic from the new layout elastic and the original layout elastic; and    a means for returning the resulting layout elastic.